Fabricating metal matrix composites containing electrical insulators
AssigneeAluminum Company of America
InventorsRalph R. Sawtell, M. K. Premkumar, David I. Yun
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Abstract
A method of fabricating a metal matrix composite containing electrically isolated areas and the MMC formed from the method. The method comprises: (a) providing a liquid pool of unreinforced aluminum alloy; (b) infiltrating the unreinforced aluminum alloy into a stack comprising upper and lower porous preforms and an electrical insulator material placed between the preforms; (c) solidifying the liquid-phase metal to form a metal matrix composite product that completely surrounds the stack; and (d) forming at least one groove in the solidified metal, the groove extending downward to at least one insulating substrate so as to electrically isolate at least one region on the surface of the metal matrix composite.
Claims31
A method of fabricating a metal matrix composite comprising the steps of:
- (a) placing at least one electrically insulating substrate on at least one porous preform in a forming chamber;
- (b) evacuating said forming chamber;
- (c) introducing liquid phase metal into said forming chamber and infiltrating said at least one porous preform and covering a surface of said at least one electrically insulating substrate with said liquid-phase metal;
- (d) solidifying said liquid-phase metal, thereby forming a composite comprising said at least one porous preform, said at least one electrically insulating substrate and a metal layer said metal layer covering said surface of said at least one electrically insulating substrate;
- and
- (e) electrically isolating at least one region of said metal layer from another region of said metal layer by removing at least a portion of said metal layer therebetween.
The method of claim I in which said liquid phase metal is an aluminum alloy.
A method of fabricating a metal composite comprising the steps of:
- (a) placing at least one electrically insulating substrate on at least one porous preform in a forming chamber;
- (b) introducing liquid phase metal into said forming chamber and infiltrating said at least one porous preform and covering a surface of said at least one electrically insulating substrate with said liquid-phase metal;
- (c) solidifying said liquid-phase metal, thereby forming a composite comprising said at least one pourous perform, said at least one electrically insulating substrate and a metal layer, said metal layer coveting said surface of said at least one electrically insulating substrate;
- and
- (d) electrically isolating at least one region of said metal layer from another region of said metal layer by removing at least a portion of said metal layer therebetween.
A method of fabricating a metal matrix composite comprising the steps of:
- (a) placing at least one aluminum nitride substrate on at least one porous silicon carbide preform in a forming chamber;
- (b) introducing liquid phase metal from the group consisting of aluminum and aluminum alloy into said forming chamber and infiltrating said at least one silicon carbide preform and covering a surface of said at least one aluminum nitride substrate with said liquid phase aluminum alloy;
- (c) solidifying said liquid phase aluminum alloy, thereby forming a composite comprising said at least one porous silicon carbide preform, said at least one aluminum nitride substrate and a metal layer, said metal layer covering said surface of said at least one aluminum nitride substrate;
- and
- (d) electrically isolating at least one region of said metal layer from another region of said metal layer or from the at least one infiltrated porous silicon carbide preform.
Dependencies are inferred from the claim text.